Sterling-Sterlco T564-02-0000 1/4" Temperature Control Valve 60°F-140°F 6' Copper Bulb 56-T-1

The Sterling-Sterlco T564-02-0000, commonly known as the 56-T-1, is a temperature sensor developed for use in a variety of HVAC  systems. It works by taking in the surrounding temperature and sending the data to the control unit of the system. For the HVAC system to operate as efficiently and comfortably as possible, a variety of functions depend on this temperature data. The liquid or gas inside the sensor's 1.25-inch copper bulb expands or contracts in response to changes in temperature. This expansion or contraction causes a change in the electrical resistance of the sensor, which the control unit reads as a temperature reading.